Purpose: :
To determine whether ultrasound treatment can promote the permeation of topical fluorescein into the vitreous.

Methods: :
Fresh cadaveric rabbit eyes were placed in saline solution at 37C. An eye cup containing 0.1% fluorescein solution was centered on the sclera approximately 5 mm posterior to the limbus. Continuous wave ultrasound at 1 W/cm2 was applied to the sclera within the eye cup for 10 minutes, and the eyes were then left in solution for an additional 50 minutes. Control eyes received the same exposure to fluorescein solution in the eye cup without ultrasound treatment. Eyes were then washed, and vitreous was collected using an automated vitrectomy system. Vitreous samples were analyzed using fluorescence spectophotometry. Fluorescence intensity levels were compared to a standard curve representing known fluorescein concentrations.